The present invention relates to a color liquid crystal display device (hereinafter referred as "color LCD") and more particularly to a color LCD comprising a liquid crystal layer formed of liquid crystal material added with a dye so as to obtain equal transmissivities of R(red), G(green) and B(blue) color filters respectively.
A color LCD in accordance with the prior art includes top and bottom glass plates, transparent conductive electrodes etched and formed on the glass plates respectively according to the predetermined arrangement, orientational layers on the interior surface of the conductive electrodes respectively, spacers between the opposite orientational layers to maintain a constant cell gap and liquid crystal materials injected between the orientational layers.
The injection of the liquid crystal materials may be embodied by a vacuum injecting method.
As is well-known, it has been found that the prior art color LCD is provided with a liquid crystal layer, which is made of any liquid crystal materials added with dopants of various kinds in connection with the cell gap and the liquid crystal twist angle.
In addition, the color LCD thus formed is provided with a two laminated structure of the cell utilizing a color effect.
The LCD, as manufactured by the prior art, allows to twist its liquid crystal material, and is capable of having the slow curve of transmissivity of light rays by interfering the rays due to the anisotropic characteristics of the liquid crystal material. In other words, there is a smooth or gradual change in the transmissivity of light rays rather than an abrupt change.
However, in the prior art color LCD thus formed, there are problems that a slight deviation of the cell gap brings about an extreme variation of the color, the cost of manufacturing the LCD is high due to a two laminated structure in order to utilize a color effect and the full and multi color effects of the LCD are not embodied practically by means of the above mentioned structure.
To utilize the color effects generally, the LCD should have the slow curve of characteristics in the transmissivity of light rays in connection with voltage power, although the determined quantity of any dopants is added to liquid crystal materials so as to twist excessively the materials.